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The white-necked rockfowl (''Picathartes gymnocephalus'') is a medium-sized bird in the family Picathartidae, with a long neck and tail. Also known as the white-necked picathartes, this passerine is mainly found in rocky forested areas at higher altitudes in West Africa from Guinea to Ghana. Its distribution is patchy, with populations often being isolated from each other. The rockfowl typically chooses to live near streams and inselbergs. It has no recognized subspecies, though some believe that it forms a superspecies with the grey-necked rockfowl. The white-necked rockfowl has greyish-black upperparts and white underparts. Its unusually long, dark brown tail is used for balance, and its thighs are muscular. The head is nearly featherless, with the exposed skin being bright yellow except for two large, circular black patches located just behind the eyes. Though the bird is usually silent, some calls are known. These rockfowl feed primarily on insects, though parents feed small frogs to their young. One feeding strategy involves following ''Dorylus'' army ant swarms, feeding on insects flushed by the ants. Rockfowl move through the forest primarily through a series of hops and bounds or short flights in low vegetation. This species rarely flies for long distances. The white-necked rockfowl is monogamous and pairs nest either alone or in the vicinity of other pairs, sometimes in colonies with as many as eight nests. These nests are constructed out of mud formed into a deep cup and are built on rock surfaces, typically in caves. Two eggs are laid twice a year. Though the birds breed in colonies, infanticide is fairly common in this species, with rockfowl attempting to kill the young of other pairs. Nestlings mature in about a month. This bird is long-lived. This species is classified as Vulnerable as its dwindling and fragmented populations are threatened by habitat destruction. Conservation efforts are underway in parts of its range in the form of habitat protection, education efforts, and new laws. Some of the indigenous peoples of Sierra Leone considered the species to be a protector of the home of their ancestral spirits. This rockfowl is considered one of Africa's most desirable birds by birders and is a symbol of ecotourism across its range. == Taxonomy == This species was first described by Coenraad Jacob Temminck in 1825 from a specimen collected on the Guinean coast. He published his description in the 2nd volume of ''Nouveau recueil de planches coloriées d'oiseaux'' and described it as ''Corvus gymnocephalus'', placing it in the crow genus ''Corvus''.〔 The species name is derived from the Ancient Greek words ''gymnos'' "naked", and ''kephalē'' "head". However, only three years later the bird was removed from the genus ''Corvus'' by René Primevère Lesson and placed in its own genus, ''Picathartes'', as it did not share characteristics common to members of ''Corvus'' such as a feathered head. This generic name comes from a combination of the Latin genera ''pica'' for "magpie" and ''cathartes'' for "vulture".〔 Since its initial description, the picathartes have been placed in more than five different families, including those of crows (Corvidae), starlings (Sturnidae), Old World flycatchers (Muscicapidae), babblers (Timaliidae) and Old World warblers (Sylviidae).〔 Today the white-necked rockfowl and its close relative the grey-necked rockfowl are believed to comprise a unique family, Picathartidae.〔 It has also been suggested though not generally accepted that the two rockfowl represent the remnants of an ancient bird order. Recent DNA analysis has shown that Picathartidae and its closest relatives, southern Africa's rockjumpers and southeast Asia's rail-babbler, form a clade. The analysis suggests that the rockfowl split from the common ancestor of their clade 44 million years ago. It is believed that the ancestor of this clade originated in Australia and spread to Africa.〔 Though the white-necked rockfowl has no subspecies, it is believed to form a superspecies with the grey-necked rockfowl, with plumage and facial pattern being the primary differences between the two species.〔 Common names used for this species include white-necked rockfowl, white-necked picathartes, yellow-headed picathartes, bare-headed rockfowl, and the less frequently used white-necked bald crow. Rockfowl is a reference to the species' habit of building mud nests on rock surfaces and caves.〔 Picathartes refers to the species' scientific name.〔 Bald crow is a reference to its featherless head and somewhat crow-like appearance, especially its beak.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「White-necked rockfowl」の詳細全文を読む スポンサード リンク
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